Harper for Obsidian
Put simply, Harper is a grammar checking plugin that doesn't violate your privacy. Other systems, like LanguageTool, ship your writing over the internet to centralized servers, where it's used for god-knows-what. Harper isn't like that.
Instead, Harper runs its grammar checking engine directly inside Obsidian. That means your data doesn't go anywhere you don't want it to. Your Obsidian vault should be just what you expect: locked down and private.
Unlike other offerings (like Grammarly) Harper also explicitly ignores the contents of code fences and inline code blocks. Since it runs entirely on-device, Harper also ends up being noticeably faster than alternatives, partly because there is no network latency.
Open Source
- Harper is fully open source, allowing transparency and community contributions to improve its functionality.
- Developers can review the codebase or contribute directly via the GitHub repository .
How It Compares to Other Plugins
| Feature | Harper | LanguageTool |
|---|---|---|
| Privacy | 100% offline | Requires self-hosting for privacy |
| Real-Time Checking | Yes | Yes |
| Language Support | English (extensible) | 30+ languages |
| Open Source | Yes | Partially |
| Ease of Use | Simple setup | Requires API/self-hosting setup |
| Performance | Fast and lightweight | Resource-intensive |
Installation Guide
- Open Obsidian and navigate to Settings → Community Plugins → Browse.
- Search for "Harper" in the plugin library.
- Click "Install" and then "Enable."
- Start typing in your notes—Harper will automatically highlight errors as you go!
Warning Harper expects an up-to-date version of the Obsidian installer. If you have issues, reinstall Obsidian or otherwise update your installer version.
Where's all the code?
All the code for the Harper Obsidian plugin lives in the main Harper monorepo . This repository exists to satisfy the requirements laid out by the Obsidian team for their plugins.
I have a problem or feature request...
Let me know if you have any problems, feature requests, or feedback of any kind by filling out an issue on the main repository .